Lens Structure

This application claims priority of Taiwan Patent Application No. 113125090, filed on Jul. 4, 2024, the entirety of which is incorporated by reference herein.

The present disclosure relates to an optical device, and, in particular, it relates to a lens structure.

In electronic products, light-emitting diodes (LEDs) are often used as light sources and are paired with various display screens to display images. However, such light sources are usually circular symmetrical light sources, and the images projected by such light sources have weaker light intensity at the edges, thereby causing uneven brightness and reducing display quality. Therefore, how to improve the non-uniformity of the circularly symmetrical light source has become an urgent issue to be solved in the art.

In some embodiments, a lens structure is provided. The lens structure includes a body having an upper surface and a lower surface, wherein the lower surface is a plane. The plane has an X direction and a Y direction, and the X direction is orthogonal to the Y direction. The body includes a first part having a first protrusion extending along the Y direction and a second part having a second protrusion extending along the Y direction, wherein the second part is arranged in parallel with the first part along the X direction. There is a depression between the first protrusion and the second protrusion, and the depression extends along the Y direction.

The lens structure of the present disclosure may be applied in a variety of electronic products. In order to make the features and advantages of the present disclosure more comprehensible, various embodiments are specially cited hereinafter, together with the accompanying drawings, to be described in detail as follows.

1 FIG. 1 FIG. 1 FIG. is a schematic diagram of the projection of an existing circularly symmetrical light source on a display screen (alternatively, it may be referred to as a projection area). As shown in the figure, in some existing electronic products, LEDs are usually used as light sources, and the light pattern emitted by such light sources is circularly symmetrical. However, the display screen DS as a projection target is mostly rectangular. Taking the schematic diagram ofas an example, the projection P (e.g., circle) of the circularly symmetric light source on the display screen DS obviously does not match the display screen DS (e.g., rectangle), especially in the edge area. Therefore, the edge of the display screen DS tends to have a dark zone DZ, causing the image to be blurred or have insufficient brightness at the edge of the display screen DS. In addition, since the illumination of light is inversely proportional to the distance it travels, the brightness of the projection P also decreases gradually from the center of the circle to the outside (such as the multiple concentric circles in), which also causes the brightness of the image to be displayed on the screen DS is not uniform. Therefore, the combination of the circular symmetrical light source and the rectangular display screen DS has a lower display quality.

In order to solve the above technical problems, the present disclosure provides a lens structure for a circularly symmetrical light source. For example, the lens structure of the present disclosure can be disposed on a circularly symmetrical light source by bonding, adsorption, embedding, tight fitting, or other methods known to a person having ordinary skills in the art. Specifically, the lens structure can focus the light source at a specific position of the display screen (or projection area) through a specific surface profile, thereby improving the problem that the existing circular symmetrical light source is obviously not suitable for a rectangular display screen. It should be noted that although LED is used as an example above, the present disclosure is not limited thereto. In practical applications, the lens structure of the present disclosure can be applied to various circularly symmetrical light sources.

In order to reduce the impact on the display, the lens structure of the present disclosure is a high light transmittance lens. In some embodiments, the material of the lens structure may include polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polycarbonate (PC), combinations thereof, or other suitable materials, but the present disclosure is not limited thereto. In some embodiments, the lens structure of the present disclosure is made of a single material, but the present disclosure is not limited thereto. For example, in some other embodiments, the lens structure may include a lens body and an optical film for improving optical properties, such as an anti-reflection film, a filter film, etc. In some embodiments, the light transmittance of the lens structure may be between 90% and 100%, but the present disclosure is not limited thereto. For example, the light transmittance of the lens structure may be 90%, 92%, 94%, 96%, 98%, 99.9%, or any value or range of the values mentioned above. In some embodiments, the light may be visible light, infrared light, or a combination thereof, but the present disclosure is not limited thereto. In other embodiments, the light may also be ultraviolet light or other suitable light.

2 5 FIGS.to 3 5 6 FIGS.,, and 1 101 102 101 102 1 101 1 102 1 101 1 102 1 are respectively a top view, a stereoscopic view, another top view, a side view, and another side view of the lens structure according to some embodiments of the present disclosure. As shown in, from the surface profile, the surfaces of the lens structuremay be roughly divided into a lower surfaceand an upper surface. The lower surfaceis a substantially flat surface, which is used to be in contact with (e.g., in direct contact with or bonded to) the circular symmetrical light source. On the other hand, the upper surfaceis a surface with a specific non-flat profile, which focuses the light leaving the lens structureat a specific position on the display screen DS through a specific curvature. In other words, when being disposed on a light source, the lower surfaceof the lens structureis adjacent to the light source, and the upper surfaceof the lens structureis facing away from the light source. The light source enters the lens structure from the lower surfaceof the lens structureand is focused on the display screen DS through the upper surfaceof the lens structure.

2 3 FIGS.and 5 FIG. 1 10 20 10 11 20 21 20 10 31 11 21 31 1 11 21 31 As shown in, from a three-dimensional structural perspective, the lens structureincludes a first partand a second part. The first parthas a first protrusionextending along the Y direction. The second parthas a second protrusionextending along the Y direction, and the second partis arranged in parallel with the first partalong the X direction that is orthogonal to the Y direction. Among them, there is a depressionbetween the first protruding portionand the second protruding portion, and the depressionextends along the Y direction. As shown in, two sides of the lens structureprotrude upward to form peaks (i.e., the first protrusionand the second protrusion), and the space between the two peaks collapses downward to form a valley (that is, depression). In the following, the lens structure will be described with some definitions to more clearly understand the spatial variation of the profile of the lens structure.

2 FIG. 3 FIG. 101 102 1 2 3 4 1 10 20 2 20 10 1 2 3 1 2 4 1 2 3 4 As shown inand, in some embodiments, a boundary between the lower surfaceand the upper surfaceis defined as an edge. In some embodiments, the edge includes a first straight edge S, a second straight edge S, a first curved edge S, and a second curved edge S. In some embodiments, the first straight edge Sis located on a side of the first partfacing away from the second part, and the second straight edge Sis located on a side of the second partfacing away from the first part. In some embodiments, the first straight edge Sand the second straight edge Sare symmetrical to each other and have substantially the same length. In some embodiments, the first curved edge Sis located between two adjacent endpoints of the first straight edge Sand the second straight edge S, and the second curved edge Sis located between the other two adjacent endpoints of the first straight edge Sand the second straight edge S. In some embodiments, the first curved edge Sand the second curved edge Sare symmetrical to each other and have substantially the same length.

1 3 1 4 2 3 2 4 1 In some embodiments, there are chamfers or rounded corners between the first straight edge Sand the first curved edge Sand between the first straight edge Sand the second curved edge S, and/or there are chamfers or rounded corners between the second straight edge Sand the first curved edge Sand between the second straight edge Sand the second curved edge S, thereby avoiding stress concentration on the corners of the lens structure.

4 FIG. 0 10 1 0 0 1 1 10 20 1 10 20 2 20 2 2 2 2 As shown in, in some embodiments, a first endpoint Ais defined on the first part, and the first straight edge Spasses through the first endpoint A. For example, the first endpoint Ais at the center point of the first straight edge S, but the present disclosure is not limited thereto. In some embodiments, a center point Ais defined between the first partand the second part. For example, the center point Ais at the center point between the first partand the second part, but the present disclosure is not limited thereto. In some embodiments, a second endpoint Ais defined on the second part, and the second straight edge Spasses through the second endpoint A. For example, the second endpoint Ais at the center point of the second straight edge S, but the present disclosure is not limited thereto.

4 5 FIGS.and 5 FIG. 5 FIG. 0 1 2 0 1 2 1 3 1 0 0 0 2 6 5 4 3 2 As shown in, in some embodiments, a first central surface contour line A along the X direction may be further defined by the first endpoint A, the center point A, and the second endpoint A. Among them, the first central surface contour line A passes through the first endpoint A, the central point A, and the second endpoint Ain sequence. In some embodiments, the lens structureis bilaterally symmetric along the first central surface contour line A. In some embodiments, the first central surface contour line A satisfies Z=−0.1209X+0.0105X−0.1909X−0.0243X+0.3506X+0.0129X+0.61, wherein −1.32≤X≤1.32, and 0≤Z≤0.8. When observed from a side (e.g., the curved edge S) of the lens structure, the first central surface contour line A has a contour as shown in. In some embodiments, the origin of the coordinate axis (i.e., coordinate (0,0)) is the point Xin, and the point Xis located at the center of the connecting line of the first endpoint Aand the second endpoint A.

4 FIG. 10 11 3 10 10 3 11 11 11 11 11 12 11 4 12 12 4 11 As shown in, in some embodiments, a first endpoint Cis defined on the first protrusion, and the first curved edge Spasses through the first endpoint C. For example, the first endpoint Cis located on the first curved edge Sand on the center line of the first protrusionalong the Y direction, but the present disclosure is not limited thereto. In some embodiments, a center point Cis defined on the first protrusion, and the center point Cis at the center point of the first protrusion, but the present disclosure is not limited thereto. In some embodiments, a second endpoint Cis defined on the first protrusion, and the second curved edge Spasses through the second endpoint C. For example, the second endpoint Cis located on the second curved edge Sand on the center line of the first protrusionalong the Y direction, but the present disclosure is not limited thereto.

4 6 FIGS.and 6 FIG. 6 FIG. 1 10 11 12 11 1 1 1 1 1 1 10 12 6 5 4 3 2 As shown in, in some embodiments, a second central surface contour line Calong the Y direction may be further defined by the first endpoint C, the center point C, and the second endpoint C. In some embodiments, the first protrusionis vertically symmetrical along the second central surface contour line C. In some embodiments, the second central surface contour line Csatisfies Z=0.5128Y−2E−14Y−1.2787Y+2E−14Y+0.0415Y−5E−15Y+0.7204 on the YZ plane formed by the Y direction and the Z direction, wherein −0.99≤Y≤0.99, and 0≤Z≤0.8. When observed from another side (e.g., a straight edge) of the lens structure, the second central surface contour line Chas a contour as shown in. In some embodiments, the origin of the coordinate axis (i.e., coordinate (0,0)) is the point Yin, and the point Yis located at the center of the connecting line of the first endpoint Cand the second endpoint C.

4 FIG. 20 21 3 20 20 3 21 21 21 21 21 22 21 4 22 22 4 21 As shown in, in some embodiments, a first endpoint Cis defined on the second protrusion, and the first curved edge Spasses through the first endpoint C. For example, the first endpoint Cis located on the first curved edge Sand on the center line of the second protrusionalong the Y direction, but the present disclosure is not limited thereto. In some embodiments, a center point Cis defined on the second protrusion, and the center point Cis at the center point of the second protrusion, but the present disclosure is not limited thereto. In some embodiments, a second endpoint Cis defined on the second protrusion, and the second curved edge Spasses through the second endpoint C. For example, the second endpoint Cis located on the second curved edge Sand on the center line of the second protrusion, but the present disclosure is not limited thereto.

4 6 FIGS.and 6 FIG. 6 FIG. 2 20 21 22 21 2 2 1 2 20 22 6 5 4 3 2 2 2 As shown in, in some embodiments, a third central surface contour line Calong the Y direction may be further defined by the first endpoint C, the center point C, and the second endpoint C. In some embodiments, the second protrusionis vertically symmetrical along the third central surface contour line C. In some embodiments, the third central surface contour line Csatisfies Z=0.5128Y−2E−14Y−1.2787Y+2E−14Y+0.0415Y−5E−15Y+0.7204 on the YZ plane formed by the Y direction and the Z direction, wherein-0.99≤Y≤0.99, and 0≤Z≤0.8. When observed from another side (e.g., a straight edge) of the lens structure, the third central surface contour line Chas a contour as shown in. In some embodiments, the origin of the coordinate axis (i.e., coordinate (0,0)) is the point Yin, and the point Yis located at the center of the connecting line of the first endpoint Cand the second endpoint C.

0 31 3 0 0 3 1 31 1 31 1 1 2 31 4 2 2 4 In some embodiments, a first endpoint Bis defined on the depression, and the first curved edge Spasses through the first endpoint B. For example, the first endpoint Bis at the center point of the first curved edge S, but the present disclosure is not limited thereto. In some embodiments, a center point Bis defined on the depression, and the center point Bis at the center point of the depression. In some embodiments, the center point Bis the same point as the center point Amentioned above. In some embodiments, a second endpoint Bis defined on the depression, and the second curved edge Spasses through the second endpoint B. For example, the second endpoint Bis at the center point of the second curved edge S, but the present disclosure is not limited thereto.

4 FIG. 6 FIG. 6 FIG. 6 FIG. 0 1 2 31 1 0 0 0 2 6 5 4 3 2 As shown inand, in some embodiments, a fourth central surface contour line B along the Y direction may be further defined by the first endpoint B, the center point B, and the second endpoint B. In some embodiments, the depressionis vertically symmetrical along the fourth central surface contour line B. In some embodiments, the fourth central surface contour line satisfies Z=0.3341Y−1E−14Y−1.0993Y+1E−14Y−0.0047Y−2E−15Y+0.6 on the YZ plane formed by the Y direction and the Z direction, wherein −0.92≤Y≤0.92, and 0≤Z≤0.6. When observing the cross section of the lens structure, the fourth central surface contour line B has a contour as shown by the dotted line in. In some embodiments, the origin of the coordinate axis (i.e., coordinate (0,0)) is the point Yin, and the point Yis located at the center of the connecting line of the first endpoint Band the second endpoint B.

4 FIG. 11 21 1 1 1 2 2 2 3 1 4 2 1 1 2 2 As shown in, in some embodiments, the first protrusionand the second protrusionare symmetrical to each other. Therefore, the shortest distance dbetween the second central surface contour line Cand the first straight edge Sis equal to the shortest distance dbetween the third central surface contour line Cand the second straight edge S. The shortest distance dbetween the second central surface contour line Cand the fourth central surface contour line B is equal to the shortest distance dbetween the third central surface contour line Cand the fourth central surface contour line B. The length Lof the second central surface contour line Cis equal to the length Lof the third central surface contour line C.

1 1 1 3 1 1 2 2 2 4 2 1 1 2 2 3 In some embodiments, the shortest distance dbetween the second central surface contour line Cand the first straight edge Smay be equal to the shortest distance dbetween the second central surface contour line Cand the fourth central surface contour line B, and the shortest distance dbetween the third central surface contour line Cand the second straight edge Smay be equal to the shortest distance dbetween the third central surface contour line Cand the fourth central surface contour line B, but the present disclosure is not limited thereto. In some embodiments, the length Lof the second central surface contour line Cand the length Lof the third central surface contour line Care both greater than the length Lof the fourth central surface contour line B.

1 1 1 In some embodiments, the applicable angle range of the lens structureis between 90 degrees and 140 degrees, but the present disclosure is not limited thereto. For example, the applicable angle of the lens structuremay be 90 degrees, 100 degrees, 110 degrees, 120 degrees, 130 degrees, 140 degrees, or any value or range of the values mentioned above. In some embodiments, the lens structuremay be applied to the light source of a home security camera, but the present disclosure is not limited thereto.

1 1 1 2 1 7 7 FIGS.A andB 8 8 FIGS.A andB 7 7 FIGS.A andB 8 FIG.A 8 FIG.B As described above, the lens structurewith the above-mentioned profile may effectively make the circular symmetrical light source more compatible with the rectangular display screen DS.are light pattern diagrams of an existing circularly symmetrical light source, andare light pattern diagrams of the lens structure according to some embodiments of the present disclosure. As shown in, from the light pattern of the existing circularly symmetrical light source, the light intensity gradually decreases from the center to the outside (that is, along the direction indicated by the arrow ARin the figure, the light intensity gradually weakens). If this light source is irradiated on the display screen DS, the uniformity of the resulting projection is only 13.6%. In contrast, when the lens structureof the present disclosure is disposed on the same circularly symmetrical light source, from the light pattern diagrams shown inand, the positions where the light intensity is the highest are concentrated on the two side (that is, the area indicated by the arrow ARin the figure has the highest light intensity). If this light source is irradiated on the display screen DS, the uniformity of the resulting projection may be as high as 44.1%. Therefore, the lens structureprovided by the present disclosure may significantly improve the problem of mismatch between the existing circularly symmetrical light source and the display screen, and provide better display quality.

The foregoing outlines features of several embodiments of the present disclosure, so that a person of ordinary skill in the art may better understand the aspects of the present disclosure. A person of ordinary skill in the art should appreciate that, the present disclosure may be readily used as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. A person of ordinary skill in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure.